Labs Values by Disease Process

Please keep in mind that all of the following lab values are for the adult patient, unless otherwise stated. We also do our very best to provide you with consistent normal ranges, however please keep in mind that these may vary depending upon your reference source. Your nursing school textbooks may reflect slightly different values. When in doubt, go with what your nursing school professors have provided, as that will be what you are tested upon.

What labs do you draw for dehydration:

The specific labs will depend on the severity of the patient’s symptoms and additional concurrent problems, but generally speaking, the following will be drawn:

They may order a CMP, which has additional labs on it, as well as a magnesium and phosphorus levels, which are not included on a BMP/CMP

UA – lets you know the concentration of the urine, if infection is present

CBC – must check the H/H, hematocrit is typically elevated

Fingerstick glucose – must get a baseline glucose, especially if the patient has a history of diabetes

Urine and/or blood osmolality – further evaluates fluid balance

What labs do you draw for infection:

If it is suspected the patient has a simple infection, there are a few labs drawn, which are outlined below. However, if a major infection is suspected and sepsis is a concern, then the labs drawn will reflect those in the following sepsis section. Cultures are drawn from wherever the infection is suspected to originate to determine the specific microorganism causing the infection. Then, an appropriate antibiotic can be selected. Examples of cultures include blood cultures (2 sets are drawn because if both reveal the same microorganism, then it is likely that is the issue… however, if only 1 set is positive, then it may be a contaminated specimen), a urinalysis with reflective culture test (or UA with reflex for short), stool culture, sputum culture, wound culture(s),cerebrospinal fluid (CSF) culture, or cultures from an invasive line (like a central line) if that is where the infection is suspected to originate.

A CBC will most likely also be ordered in addition to cultures to determine the source of infection. They are looking closely at the WBC count, as an elevation in this is an indicator of infection.

What labs do you draw for sepsis:

All. All of the labs.

Haha, just kidding. But seriously, there are a LOT of labs to draw for sepsis.

These are all very important and it is essential to obtain them in a timely matter because with sepsis, time is of the essence. Also, it is absolutely imperative that your cultures are drawn BEFORE initiating antibiotics. The “golden hour” of sepsis is initiating antibiotics within the first hour, which means that you must draw your labs FAST.

CMP with anion gap – checking for any electrolyte disturbances so we can correct them, assess renal function

Magnesium, Phosphate – not part of the CMP, but electrolytes and assessed to identify any imbalances

Goal is to correct any electrolyte balances

CBC with diff

WBC – may be really high or low

% of bands affected is important (and % of of bands only show up on a CBC WITH differential, so important to make sure you’re getting the diff). Bands are the percent of immature WBC’s, so if you have a high percent of them, that’s really concerning

3% is normal

If greater than 10% of immature WBC’s, we’re worried

“Shift to the left” is a quantitative way of showing that there is an abnormally high level of immature cells… rather than % of bands, which is quantitative and can be inaccurate

Platelets – 150,000 – 450,000 is normal… may be high or low

H/H – may be low, and will transfuse typically if HgB less than 10 to provide as much oxygenation to the tissues as possible

Type and screen – blood products frequently administered and it’s essential to get a baseline of the patient’s blood type right away so that they can be administered ASAP when needed

ABG – evaluating the level of organ compromise and severity of metabolic acidosis, serial ABG drawn… gives us baseline, allows us to evaluate treatment course and adjust as needed

PT/INR, PTT – bleeding times can be prolonged so you really need to know what you’re working with and get a baseline, and follow up as needed

PT: 11 – 13

PTT (not on anticoagulant therapy): 25 – 35 seconds

On therapy = can be double normal, or but specific range depends on reason for therapy

INR (not on anticoagulant therapy): 0.8-1.2

On therapy: roughly 2-3, but can differ depending on reason for therapy

CK Isoenzymes/Troponin – even without symptoms of ACS, about 85% of septic patients will have elevated cardiac markers. Essential to establish baseline at admission so we know what we’re working with

CK: 55-170 units/L

Troponin: < 150 mg/dL

Lactic acid (venous or arterial) – a global marker for tissue oxygenation and therefore important to assess with sepsis. Basically, not enough oxygen is getting to the tissues when you have an increased lactic acid lab. The higher the value, the worse it is.

Normal is less than 0.3-26 mmol/L, if it’s greater than 4… that’s bad news bears

What labs do you draw for diabetes mellitus (DM):

There are a few labs to ascertain whether or not a patient is newly diagnosed with diabetes, which include a fingerstick glucose (needed immediately!) as well as a Hemoglobin A1C (not as urgent, but necessary during admission… abbreviated as HgbA1C).

You’ll be monitoring glucose frequently during their admission. The exact frequency depends on the actual level. It could be taken as frequently as every 15 minutes, only before meals, before and after meals, every 6 hours, and so forth. If able, the physician will likely order a fasting blood glucose.

A lipid panel may be ordered to assess hyperlipidemia, when if present with diabetes really increases the risk for heart disease.

The HgbA1C tells you how well their blood sugar has been controlled over the last 3 months.

What labs do you draw to assess hepatic function:

A liver panel, hepatic panel, or liver function tests (LFT’s) are drawn to assess the liver. While there can be more drawn than this to get even more specific, generally speaking… assessing the liver with labs includes these values: ALT, AST, ALP (all of which are typically elevated if there’s an issue), total and indirect bilirubin (again, increased), albumin and total protein (typically decreased if a problem is occurring).To summarize: ALT, AST, ALP, total and indirect bilirubin, albumin and total protein

What labs do you draw for fluid volume excess:

BMP: sodium levels are particularly essential in fluid volume excess (we expect to see hyponatremia in this case), and just checking the other electrolytes to see if correction is needed… as well as a BUN which is probably decreased

Serum osmolality (or serum osmo for short!) – most likely decreased

CBC: checking the hematocrit specifically, which is probably decreased

To summarize: BMP, serum osmo, CBC

What labs do you draw for myocardial infarction (MI):

Cardiac biomarkers: troponin I, troponin T, CK, CK-MB, myoglobin

If a patient also have heart failure, most likely BNP and pro-BNP will also be ordered

CMP: necessary to know creatinine if the patient will be going for a cardiac cath, also to know electrolyte levels as electrolyte imbalances can make things worse (potassium and magnesium specifically)

CBC: trying to rule out if anemia caused the MI by checking out the H/H… WBC may be slightly elevated in MI, and must assess platelets if certain meds are to be given

Lipid profile: not an urgent lab, but should be drawn if statin therapy is to be initiated

What labs do you draw for congestive heart failure (CHF):

Various labs are necessary to draw, but one single lab won’t confirm diagnosis. You must consider the entire clinical picture and diagnostics in addition to the below labs. All are important, but the BNP is a big one for CHF.

CBC – H/H

Anemia is a cause of CHF

Must get baseline!

CMP – get a baseline electrolytes, kidney, liver situations… as these can be out of normal range due to the disease process and meds patients with CHF take at home

Cardiac enzymes – increase in cardiac markers in CHF can help support the severity of the exacerbation (source)

CRP – inflammatory marker, elevated with an infectious process

5-10 is normal

T3, T4 – levels that are too high or too low can contribute to cardiac issues and correcting the thyroid issue may resolve the dysrhythmia, which would address the CHF

BNP and pro-BNP: amino polypeptide secreted by ventricles in response to ventricular stretching

BNP: normal is less than 100 pg/mL

Pro BNP: males is less than 60 pg/mL, females is 12-150

To summarize: CBC, CMP, cardiac enzymes, CRP, T3, T4, BNP, pro-BNP

What labs do you draw for urinary tract infection (UTI):

The main lab in this case is a urinalysis with reflexive culture. This will identify the kind of microorganism so that the appropriate antibiotic can be initiated. Also, a CBC will most likely also be ordered. They are looking closely at the WBC count, as an elevation in this is an indicator of infection.To summarize: UA with reflex, CBC

What labs do you draw for disseminating intravascular coagulation (DIC):

If a patient potentially has DIC, they’re one sick pup. Many labs may be ordered, but these are the standard labs drawn to come to the DIC diagnosis:

Fibrinogen degradation products (FDP’s)- increased, but this is non-specific

D-Dimer – increased, but this is non-specific

To summarize; CBC, aPTT, PTT, FDP’s, D-Dimer

What labs do you draw for pneumonia:

CBC with or with differential

WBC – most likely elevated (over 10,000)

H/H – assessing to see how compromised they may be, could be low

Hemoglobin (HgB)

Male: 14-17 g/dL

Female: 12-15 g/dL

Hematocrit (HCT)

Male: 42-52%

Female: 36-46%

BMP or CMP – necessary to ensure there are no baseline electrolyte imbalances that need to be corrected or existing renal impairment, as antibiotics will most likely be initiated and have the unlikely side effect of nephrotoxicity

K: 3.5-5 mEq/L

Cl 98-108 mEq/L

BUN 5-20 mmol/L

Creatinine 0.6-1.2 mg/dL

ABG’s – assessing the level of respiratory compromise

Blood cultures – draw BEFORE any antibiotics are started

Sputum culture – if patient is producing sputum

Therapeutic drug levels – patients are typically started on antibiotics and it’s important to see if the dosages are correct

Typically ordered to be drawn 30 minutes before next dose is administered

Coagulation studies like PT, PTT: clotting factors are produced by the liver, so if cirrhosis is going on, you may have some abnormal coags, which is essential to know

There are many additional labs that can be ordered, depending on the circumstance. If ascites is also present, the fluid most likely will be analyzed. They may be tested for Hep B or C if not already diagnosed.

To summarize: CMP, CBC, PTT, PT

What labs do you draw for GI bleed:

CBC with diff – most likely drawn multiple times to address the effectiveness of treatment

H/H – determines how much blood to administer and the degree of loss

Platelets – checking for thrombocytopenia

BMP

Calcium – most likely low

Electrolyte baseline to correct as needed (a mag and phos may be added, which are not included in a BMP)

What labs do you draw for stroke:

These are the basic labs drawn when a patient is diagnosed with a stroke. Please keep in mind there are both ischemic and hemorrhagic strokes, and additional labs may be ordered for varying degrees of severity, as well as if something else is going on with the patient.

Glucose – hypoglycemia can present similarly to stroke, therefore it is imperative to get a fingerstick and quickly assess the blood sugar before implementing an entire stroke protocol

Hypoglycemia is defined as a blood sugar less than 70

Glucose is collected as part of a BMP/CMP, however it’s helpful to get a quick fingerstick to rule out hypoglycemia rather than wait for the BMP/CMP to result

Patient may receive an MRI or CT with contrast and we must know if they have any kidney compromise, as the contract dye could put them into acute renal failure

Diabetes can go hand in hand with stroke, must assess kidney function, as it can be compromised due to uncontrolled diabetes

Liver

Albumin, bilirubin, protein, ALT, AST

If started on statins, as most patient with an ischemic stroke are, you must get a baseline of their liver function, as statins are hard on the liver

Lipid panel – this drawn specifically for ischemic stroke, as we want to see if they have a drastically elevated serum level of lipoproteins and/or cholesterol, and if that could be the cause of the stroke. Also must evaluate if the HDL are too low, which can promote the inflammatory response (source).

HDL, high density lipoproteins: greater than 60

LDL, low density lipoproteins: less than 100

Triglycerides: less than 150

Total cholesterol: less than 200

Hemoglobin A1C – people with diabetes are 2-4x more likely to have a stroke than non-diabetics (source), so even if someone is currently diagnosed with diabetes, assessing their blood sugar control over the last 3 months by checking an HgbA1C can be helpful

CBC – when patients present with an acute ischemic stroke, the immediate goal is to see if they are a candidate for tPA. One of the exclusionary criteria for tPA administration is if their platelets are less than 100,000. That’s

PT/INR, PTT – many patients who have suffered from an ischemic stroke were on anticoagulant or antiplatelet therapies for varying reasons. While these blood thinning therapies are very effective at reducing stroke, they don’t completely negate the risk. And if they’ve had a hemorrhagic stroke, we’ve got to know where their coags are, so we know what to administer and how much if they are elevated.

PT: 11 – 13

INR (not on anticoagulant therapy): 0.8-1.2

On therapy: roughly 2-3, but can differ depending on reason for therapy

PTT (not on anticoagulant therapy): 25 – 35 seconds

On therapy = can be double normal, or but specific range depends on reason for therapy

What labs do you draw for Hepatitis B:

There are three different Hep B tests you can do. The selection of which depends on the circumstances… so if you want to see if a vaccinated person still has immunity… if someone is suspected of having Hep B…. or if you’re trying to figure out if it’s acute versus chronic.

The Hepatitis B surface antigen test (or HBsAG) detects a protein that’s present on the surface of the virus. This is typically done in the patient you’re thinking may have Hep B, a Hep B screening (so if you experience an accidental needlestick and need to see if the patient has Hep B, they’ll draw this lab).

The Hepatitis B surface antibody test (or anti-HBs) detects any antibody produced in response to the Hep B surface antigen. Essentially, this is done when you’re checking to see if a vaccinated person has immunity (so if you were vaccinated as a child and are now applying to nursing school, this lab may be drawn to see if you still have immunity and whether or not you need a booster). This can also be drawn if someone previously had an infection and we’re seeing it they’re immune,

Finally, the total anti-hepatitis B core tests (or anti-HBc, IgM and IgG) detect the following antibodies: Hepatitis B, IgM, IgG. This is done when you’re trying to figure out if this is a chronic versus acute situation. IgM is produced first, and then IgG presents itself later on and hangs around for the rest of the patient’s life typically. (Source)

What labs do you draw for clostridium difficile (c. diff):

Basically, diagnosing c.diff is a 2-step process. If it is suspected a patient has c.diff, a stool sample is collected and a non-specific screening is performed. This tests for the c. diff antigen. So this antigen is produced in high amounts by c.diff, but isn’t specific to toxin-producing c.diff, which is what we care about. So if this screening test comes back positive, another test is performed.

(Typically, the nurse is sending down the stool sample, and this 2-step process is taken care of within the lab by their own processes.) A toxigenic stool culture is the gold standard in this 2-step process, but takes about 2-3 days to result, and doesn’t tell you if it’s a colonization versus overgrowth or infection… therefore, another test has to be completed so you know which treatment course to take. Also, when a patient is pretty sick in the hospital, finding out in 2-3 days isn’t always great. The other option is a PCR assay, which results quickly and is very sensitive and reliable… but not all labs have the capabilities for this particular test.

What lab values do you need to know for NCLEX?

There are quite a few labs to know to be successful with the NCLEX. Please note that just because something is listed below doesn’t mean you will definitely see it on the exam.

Most common labs: RBC, HGB, HCT, PLT, WBC, PT, INR/PTT, Albumin, Creatinine, BUN, Glucose, HBGA1C, BNP, UA, Troponin I, Cholesterol, Ammonia, Total Bilirubin, Lactic Acid, ABG’s. We created an entire course which focuses solely on these labs. You can check it out here, or as part of our NRSNG Academy, along with ten other courses.

How to chart lab values:

The manner in which a nurse charts lab values is heavily dependent upon the policies and procedures of the institution in which you’re working. Many times, the labs are automatically posted and charted by the lab department and as the nurse, you merely need to chart that you’ve reviewed them.

However, if you need to actually type lab values into the chart there are a few things to remember:

Always chart the exact value; don’t approximate

Correct: 7.5 mmol/dL

Incorrect: about 7

Always include the unit of measurement

Correct: 7.5 mmol/dL

Incorrect: 7

Always double check you are charting the correct lab value in the correct patient’s chart

It can be much easier than you would think… it is very easy to be thinking about one patient and have another patient’s chart open. Double check for accuracy.

If it is a critical lab value (abnormally high or low), make sure you chart who you notified, when, and any orders you received. Many institutions have specific charting requirements for

Correct: “Critical lab result of Potassium 2.5 mEq/L on 4/28/17 at 1509. Dr. Markson notified at 1520. Orders for potassium replacement and follow-up BMP after administration received, please see MAR for order specifics.”

Incorrect: “Potassium 2.5. Orders received.”

Lab values: fishbone

Lab fishbones are basically a quick way to write out labs during report where you don’t have to write out the name of the lab, merely the value, in a consistent location. It makes writing down and referencing information for report significantly faster. Seriously. Nurses love these things.

However, the trick is that not everyone writes them the same. There isn’t an ironclad specific way you must do this or die a painful NCLEX death. This is because you are writing these on your personal report sheet, not the patient’s medical record.

(If for some reason you are handwriting these in a patient’s medical record, you must follow your institution’s policy on these precisely.)

What is important is that you do it the same way every time. Consistency is key, people! If you keep changing it up, you won’t know which lab is which… and that defeats the purpose. Also, don’t give up too soon on learning these. It can be frustrating at first to learn where things go, but once you get the hang of it, it’ll be smooth sailing.

Consistency is key, people! If you keep changing it up, you won’t know which lab is which… and that defeats the purpose. Also, don’t give up too soon on learning these. It can be frustrating at first to learn where things go, but once you get the hang of it, it’ll be smooth sailing. Check out this Lab Values Skeleton Cheatsheet here with skeleton examples for CBC, liver enzymes, ABG, BMP, Chem-10, liver profile, and bleeding times!

What lab values do you monitor with isotretinoin (Accutane)?

Routine lab monitoring has been the standard for patients taking isotretinoin, however recently that’s been reexamined to determine if it’s necessary.

Currently, triglycerides, ALT (alanine aminotransferase), WBC, and platelets are monitored. (Essentially, a lipid panel, CBC, and hepatic panel.) This is done either weekly, biweekly, or monthly until they’re able to gauge response has been doneArticle and study discussing this evolving standard!

What lab values do you monitor with valproic acid (Depakote)?

A valproic acid test, which let’s you know if the dose is therapeutic or needs to be adjusted is very important (the therapeutic range for total valproic acid is currently 50-125 µg/mL, and for free valproic acid it is 6-22 µg/mL). Also, liver function tests (ALT, AST) and a CBC is monitored.

What lab values do you monitor with heparin?

If a patient has a continuously infusing heparin drip, typically an aPTT is drawn at routine intervals. This lets you know if you need to increase, decrease, or maintain your dosage. It is drawn more frequently at first (typically every 6 hours until therapeutic – it’s TIMED and therefore essential to draw it promptly when due) and then possibly every 12-24 hours while therapeutic. The therapeutic range is dependent upon the reasoning for the drip in the first place.

However, some institutions draw an anti-Xa rather than an aPTT to determine the therapeutic level of heparin in the blood.

A CBC, PT/INR, PTT, and bleeding time is also frequently assessed at baseline. It’s helpful to know where the patient started before heparin was initiated with these various values so that when reassessed, we can see how much they’ve adjusted. If you think your patient has heparin-induced thrombocytopenia, or HIT, you will draw a HIT panel. Roughly 3% of patients receiving heparin will develop HIT (source). A HIT panel includes serotonin release assay (SRA), unfractionated heparin, and heparin-induced platelet antibody.

What lab values does heparin effect?

PTT, Anti-Xa – monitoring one of these and titrating appropriately is the normal process. Platelets – we monitor these, but hoping not to see a change or decrease below 100,000… otherwise the patient may be developing heparin-induced thrombocytopenia. To monitor platelets, you would draw a CBC.

What lab values do you monitor with furosemide (Lasix)?

When initiating furosemide, it’s helpful to initially monitor quite a few values. The frequency of lab monitoring really depends on how much they are getting and what route. (For example, a patient being started on 20 mg orally once a day versus someone with a continuous IV infusion.) Regardless of frequency, it’s essential to monitor electrolytes (potassium in particular) and kidney function. This can be done with a BMP or CMP and a magnesium level.

What lab values do you monitor with lithium?

The lithium test is required to assess the therapeutic level of lithium. Currently, the therapeutic range is 0.6-1.2 mmol/L. However, whenever someone is initially being started on lithium, a baseline CBC, BMP, lipid profile, fasting glucose and hepatic panel are drawn.

What lab values do you monitor with enoxaparin (Lovenox)?

CBC (specifically looking at platelets), hemoccult (to check for bleeding) at varying intervals is typically completed. Coags are monitored when enoxaparin is given for prophylaxis, like the PTT, aPTT, and anti-Xa. To check renal status or if a patient has a history of renal issues, checking a BUN and creatinine is a good idea (BMP).

Wondering what lab values you need to know as a nurse?

While there are literally THOUSANDS of lab values that you can learn, it would be impossible to do so . . .

As you begin working as a nurse on a specialized unit you will have to learn different labs that are important to that field.

Bleeding Time Lab Values

Abbreviation

APTT

Normal Range

25-39 seconds

Description

APPT is a test that measures the amount of time it takes for a fibrin clot to form after reagents have been added to the specimen. It is useful in diagnosis clotting disorders. In conjunction with PT it can be used to differentiate the specific factor that may be missing.

Indications

Identifying

Congenital deficiencies in clotting

Monitoring

Effects of liver disease

Protein deficiency

Fat malabsorption on clotting

Increased Levels

Vitamin K deficiency

DIC

Patients on hemodialysis

Afibrinogenemia

Polycythemia

Liver disease

Von Willebrand disease

Decreased Levels

Abbreviation

ALT

Normal Range

13 – 69 U/L

Description

ALT is an enzyme made in the liver. This enzyme is found in highest concentrations in the liver , but is found to lesser extent in heart, skeletal muscle and kidney. Damage to the liver results in a significant increase in this enzyme.

Indications

Monitoring

progression of liver disease or liver damage

It can also aid in monitoring response to treatments

Increased Levels

Cirrhosis

Muscle damage

Preeclampsia

Biliary tract obstruction

Burns

Pancreatitis

Long-term alcohol abuse

Liver Cancer

Muscular dystrophy

MI

Myositis

Shock

Infections mononucleosis

Decreased Levels

Normal Range

3.5 - 6.0 g/dL

Description

Albumin is a transport protein in the blood. It helps maintain the oncotic pressure of the blood. Albumin levels will drop if synthesis is slowed, protein intake is inadequate, or there are increased losses. Albumin has a long half life, however, so levels are not a good indicator of acute illness.

Normal Range

40-130 U/L

Description

Alkaline phosphatase (ALP) is located in several places in the body: liver, intestines, biliary tract, bones, placenta. Different isoenzymes of ALP can be used to determine different disorders: liver, bone, intestine, certain cancers. It can also be used to determine bone turnover in postmenopausal women.

Indications

Identifying

Hepatobiliary disease

Malignancies

Bone disease

Bone damage in renal patients

useful in evaluating bone growth in children.

Increased Levels

Liver disease

Bone disease

Pregnancy

Amyloidosis

Lung cancer

Pancreatic cancer

Congestive heart failure

Ulcerative colitis

Hodgkin’s disease

Chronic renal failure

Sarcoidosis

Decreased Levels

Abbreviation

NH3

Normal Range

19-60 mcg/dL

Description

Ammonia (NH3) is a byproduct created when protein is broken down. Ammonia is converted into urea in the liver, and urea is excreted by the kidneys. During liver disease, ammonia levels rise and can have a negative effect on the brain.

Decreased Levels

Abbreviation

AST

Normal Range

12-37 U/L

Description

Aspartate aminotransferase (AST) is an enzyme primarily found in liver and heart cells and to a smaller extent, AST can also be found in the pancreas, kidneys, skeletal muscle, and brain. Levels of AST increase from cell death (necrosis) because the AST enzyme is released into the blood.

Increased Levels

Decreased Levels

Abbreviation

Ca+

Normal Range

8.4-10.2 mg/dL

Description

Calcium (Ca+), a positive ion in the body, is necessary for neuromuscular processes, bone mineralization, and hormonal secretion. The parathyroid gland and vitamin D are responsible for calcium regulation in the body. In the blood, about half of calcium travels in ion form, the other half is bound to proteins like albumin. When albumin levels are low, calcium levels will appear lower. Calcium has an important relationship with phosphorus: they are inversely proportional.

Abbreviation

Cl-

Normal Range

96-108 mEq/L

Description

Chloride (Cl–), an anion found in the blood, works together with sodium to help maintain oncotic pressure and water balance in the body. Chloride is inversely related to bicarbonate levels in the blood. Chloride is also part of hydrochloric acid (HCL) which is utilized in the stomach to breakdown food. When Red Blood Cells (RBCs) take up CO2 they take up chloride as well. The negative ion bicarbonate then leaves the red blood cell so that the electrical charge is maintained. Extra chloride is excreted into the urine by the kidneys.

Abbreviation

Chol

Normal Range

<200 mg/dL

Description

Cholesterol (Chol) is a lipid in the body. It is a part of cell membranes as well as a precursor for vitamin D, steroids, and bile acids. Cholesterol is primarily synthesized in the liver and intestines and is transported via lipoproteins. There are multiple types of lipoproteins, each have slightly different functions. The two most common types of lipoproteins are high-density lipoprotein (HDL) and low-density lipoprotein (LDL).

Decreased Levels

Abbreviation

CK

Normal Range

55 - 170 U/L

Description

Creatine kinase (CK) enzyme is found in heart and skeletal muscle and to a lesser extent brain. When damage is done to these types of tissue CK is released into the blood. There are three isoenzymes, and depending on which one is elevated this lab value can help determine timing, location, extent of damage. The three isoenzymes are CK-MB (cardiac), CK-MM (skeletal), and CK-BB (brain).

Decreased Levels

Normal Range

85 to 125 mL/min

Description

Creatinine is a byproduct of Creatine metabolism, and it is excreted in the kidneys. Creatinine is created in proportion to muscle mass and usually stays stable. Urine and blood levels are compared to determine creatinine clearance from the blood. Any disease that affects the kidneys ability to clear waste products will increase blood creatinine levels and decrease creatinine clearance levels.

Indications

Used to determine:

Kidney damage in renal disease

Glomerular function

Effectiveness of treatment

Increased Levels

Diabetes Mellitus (DM)

Exercise

Pregnancy

High protein diets

Decreased Levels

Abbreviation

DDI

Normal Range

≤ 250 ng/mL

Description

D-dimer (DDI) is a product of fibrinolysis, the process of plasminogen breaking down fibrin clots. Two products are made by fibrinolysis: D-dimer (DDI) and Fibrin Degradation Products (FDP). D-dimer levels are elevated in the setting of clot breakdown, but will be even higher in the setting of Disseminated Intravascular Coagulation (DIC).

Indications

Identify and monitor Disseminated Intravascular Coagulation (DIC)

Rule out a blood clot:

Pulmonary Embolism (PE)

Deep Vein Thrombosis (DVT)

Stroke

Increased Levels

Surgery

Trauma

Infection

Cancer

Heart attack

Pregnancy

Deep Vein Thrombosis (DVT)

Disseminated Intravascular Coagulation (DIC)

Decreased Levels

Abbreviation

ESR

Normal Range

0-20 mm/h

Description

The Erythrocyte Sedimentation Rate (ESR) test measures sedimentation of Red Blood Cells (RBCs). The inflammatory process affects proteins in the blood which causes RBCs to stick together and settle out of liquid. Normal blood has very little settling, but during the inflammatory process the ESR is elevated.

Indications

Identifies inflammation which assists in diagnosing:

Cancer

Infection

Autoimmune diseases

Increased Levels

Anemia

Chronic Renal Failure

Systemic Lupus Erythematosus (SLE)

Infection

Tuberculosis

Pregnancy

Polymyalgia Rheumatica

Multiple myeloma

Medications:

Oral contraceptives

Theophylline

Vitamin A

Decreased Levels

Normal Range

20-300 ng/mL

Description

Ferritin is a protein that stores iron. It is formed in the liver spleen and bone marrow. Ferritin in the blood is usually proportional to stored ferritin. Ferritin is a more sensitive and specific test for identifying iron-deficiency anemia, however, it is usually measured in conjunction with total iron binding capacity and iron.

Decreased Levels

Normal Range

70-115 mg/dL

Description

Glucose is a sugar molecule that is a component of carbohydrates. Glucose provides energy in the body and is absorbed from the blood to the cells for nourishment via insulin. The pancreas secretes insulin to helps regulate levels of glucose in the blood. Glucose levels naturally rise after meals with the intake of carbohydrates.

Indications

Diagnose:

Hypoglycemia

Hyperglycemia

Diabetes Mellitus (DM)

Monitor treatments for Diabetes Mellitus (DM)

Increased Levels

Diabetes Mellitus (DM)

Stress

Pancreatitis

Chronic Renal Failure

Cushing Syndrome

Corticosteroid therapy

Decreased Levels

Abbreviation

HbA1c

Normal Range

5.6-7.5 % of total Hgb

Description

Glycosylated Hemoglobin (HbA1c) is the combination of glucose and hemoglobin. When glucose is elevated in the blood the amount of glycosylated hemoglobin increases proportionally. A red blood cells lifespan is about 4 months, so you can get an idea of blood sugar control over the last several months.

Abbreviation

HDL

Normal Range

>60 optimal mg/dL

Description

Cholesterol is transported via lipoproteins. There are multiple types of lipoproteins and they each have slightly different functions: high-density lipoprotein (HDL), low-density lipoprotein, LDL, very low-density lipoprotein (VLDL). HDL cholesterol is considered the good cholesterol because it travels through the blood picking up extra cholesterol and taking it back to the liver.

Decreased Levels

Abbreviation

Fe

Normal Range

50-175 ug/dL

Description

Iron (Fe) is an element that is an important component of hemoglobin in red blood cells. Hemoglobin transports oxygen from the lungs to all the cells of the body. Most of the iron in the body is located in hemoglobin, but some iron is located in myoglobin as well as some iron is stored in the liver, bone marrow, and spleen. The storage form of iron is ferritin. Iron is transported in the blood by a protein called transferrin.

Decreased Levels

Normal Range

0.3 -2.6 mmol/L

Description

Lactate (Lactic Acid) is a byproduct of anaerobic metabolism. Normally, the tissues use aerobic metabolism to breakdown glucose for energy and the byproduct is CO2 and H2O which we excrete through our kidneys and exhalation. However, if the tissues are starved of oxygen (hypoxic), they use anaerobic metabolism. This can be compounded if the liver is also hypoxic causing the liver to be unable to clear the lactic acid.

Indications

Determine cause of acidosis

Evaluate tissue oxygenation

Increased Levels

Shock

Sepsis

Tissue ischemia

Carbon monoxide poisoning

Lactic acidosis

Diabetes Mellitus (DM)

Heart failure

Pulmonary edema

Strenuous exercise

Decreased Levels

Normal Range

23 - 300 U/L

Description

Lipase is an enzyme created in the pancreas. It travels to the intestines where it aids in the breakdown of fats. If damage occurs to certain parts of the pancreas, lipase is released into the bloodstream.

Indications

Diagnose:

Pancreatitis

Pancreatic cancer

Increased Levels

Pancreatitis

Pancreatic cyst

Pseudocyst

Pancreatic duct obstruction

Renal failure

Cholecystitis

Peptic ulcer disease

Decreased Levels

Abbreviation

LDL

Normal Range

<70 mg/dL

Description

Cholesterol is transported via lipoproteins. There are multiple types of lipoproteins and they each have slightly different functions: high-density lipoprotein (HDL), low-density lipoprotein, LDL, very low-density lipoprotein (VLDL). LDL cholesterol is considered bad cholesterol because as it travels through the blood, it deposits cholesterol into the lining of blood vessels, causing atherosclerosis and an increase in cardiovascular disease.

Decreased Levels

Abbreviation

SaO2

Normal Range

95 - 100%

Description

Oxygen saturation (SaO2) is a measurement of the percentage of how much hemoglobin is saturated with oxygen. Oxygen is transported in the blood in two ways: oxygen dissolved in blood plasma (pO2) and oxygen bound to hemoglobin (SaO2). About 97% of oxygen is bound to hemoglobin while 3% is dissolved in plasma. SaO2 and pO2 have direct relationships, if one is decreased so is the other. The relationship between oxygen saturation (SaO2) and partial pressure O2 (PaO2) is referred to as the oxyhemoglobin (HbO2) dissociation curve. SaO2 of about 90% is associated with PaO2 of about 60 mmHg. For more information on PaO2, SaO2 and oxyhemoglobin dissociation curve visit this link HERE.

Decreased Levels

Abbreviation

PTT

Normal Range

25 - 35 seconds

Description

Partial Thromboplastin Time (PTT)evaluates the function of factors I, II, V, VIII, IX, X, XI, and XII. PTT represents the amount of time required for a fibrin clot to form. Monitors therapeutic ranges for people taking Heparin.

Indications

Detection of coagulation disorders

Evaluate response to Heparin (PT for Coumadin)

Preoperative assessment

Increased Levels

Disseminated Intravascular Coagulation (DIC)

Clotting Factor Deficiencies:

Hypofibrinogenemia

Von Willebrand Disease

Hemophillia

Liver disease:

Cirrhosis

Vitamin K deficiency

Polycythemia

Dialysis

Decreased Levels

Abbreviation

(PLT)

Normal Range

100,000 - 450,000 cells/mcL

Description

Platelets (PLT) play a role in coagulation, hemostasis, and thrombus formation. Platelets are the smallest blood cell, damaged vessels send out signals that result in platelets traveling to the area and becoming “active”.

Abbreviation

K+

Normal Range

3.5 - 5.0 mEq/L

Description

Potassium (K+) is the most abundant intracellular cation and plays a vital role in the transmission of electrical impulses in cardiac and skeletal muscle. It plays a role in acid base equilibrium. In states of acidosis hydrogen with enter the cell as this happens it will force potassium out of the cell, a 0.1 decrease in pH will cause a 0.5 increase in K+.

Increased Levels

Decreased Levels

Abbreviation

RBC

Normal Range

Male: 4.5 - 5.5 x106/cells/mm3 Female: 4.0 - 4.9 x106/cells/mm3

Description

Red Blood Cells (RBCs) contain hemoglobin which is responsible for oxygen transport throughout the body. RBCs are primarily produced in the bone marrow, they have a life span of 120 days and are destroyed in the spleen and liver. RBC production is regulated by erythropoietin (EPO) which is produced and released from the kidneys.

Abbreviation

Na+

Normal Range

135-145 mEq/L

Description

Sodium (Na+) is the most abundant cation in extracellular fluid. Sodium aids in osmotic pressure, renal retention and excretion of water, acid-base balance, regulation of other cations and anions in the body, plays a role in blood pressure regulation, and stimulation of neuromuscular reactions. Sodium and water have a direct relationship; Water follows salt.

Abbreviation

TSH

Normal Range

2-10 mU/L

Description

Thyroid Stimulating Hormone (TSH) is released from the pituitary in response to low levels of thyroid hormone. TSH communicates to the thyroid gland to release the thyroid hormones: Triiodothyronine (T3) and Thyroxine (T4). Thyroid hormones regulate metabolism. T3 and T4 have and inverse relationship with TSH.

Indications

Diagnose:

Hyperthyroidism

Hypothyroidism

Monitor thyroid replacement therapy

Increased Levels

Hypothyroidism

Thyroidectomy

Thyroid dysfunction

Thyroiditis

Thyroid Agenesis

Large doses of iodine

Pituitary TSH-secreting tumor

Decreased Levels

Abbreviation

T. Billi

Normal Range

0.1 - 1.2 mg/dL

Description

Total Bilirubin (T.Billi) is the sum of conjugated and unconjugated serum bilirubin. One of the byproducts of red blood cell breakdown is bilirubin. Bilirubin is made in the bone marrow, liver, or spleen and is transported by albumin to the liver in the form of unconjugated bilirubin. Once in the liver, sugars bind to the unconjugated bilirubin, turning it to conjugated bilirubin. It is then excreted from the gall bladder into the small intestine. Eventually, it is excreted in the feces or urine. Excess bilirubin causes a yellowing of the skin and the whites of the eyes called jaundice.

Decreased Levels

Abbreviation

cTNL

Normal Range

There is a wide range of normal values among varying institutions and texts with regard to Troponin I. It is essential to verify institutional norms. < 0.035 ng/mL

Description

Troponins are proteins that initiate contraction of muscle fibers. Troponin I (cTNL) is specific to heart muscle. Troponin levels stay elevated for a week after muscle damage before returning to normal.

Indications

Evaluating damage to heart muscle

Diagnose a Myocardial Infarction (MI)

Increased Levels

Heart damage

Myocardial Infarction (MI)

Decreased Levels

Abbreviation

WBC

Normal Range

4,500 - 10,000 cells/mcL

Description

White blood cells (WBCs) are created in the bone marrow. Their primary function is to defend the body against infection. There are various types of WBCs which have different shapes and functions. Decreased WBC count is called Leukopenia and increased WBC count is called Leukocytosis.

Decreased Levels

How to Study Lab Values so You Remember

Like everything else in nursing school, learning lab values is like learning a whole new language.

Prior to nursing school I knew what Potassium, Sodium, RBCs, WBCs, blood sugars, and a few other BIG laboratory values were, but I didn’t have a real grasp on what they meant.

When a patient comes into the hospital you will find that the only number they usually want to know from a laboratory panel is the blood glucose . . . their “sugars” . . .

The patient WANTS to be involved in their health care, but they really don’t know what a Lactic Acid level is and why we care.

To work as a competent member of the health care team it is important that you not only learn the important lab values but also what they mean.

This helps you in a few ways:

You can anticipate what labs will be ordered on a given patient

You can talk (with knowledge) to providers about a patients care

You can educate family members and patients

You stop being a task rabbit that is just drawing blood and actually become a member of the health care team

So let’s talk about a few ways you can study to actually retain laboratory value information:

Determine the most essential labs for your floor – as I’ve mentioned a few times . . . it’s impossible to learn EVERY lab value. Start be determining which values you REALLY need to know to do a good job on your floor. If you work on a cardiac floor . . . learn all you can about your cardiac enzymes. If you work ICU . . . learn about your sepsis labs, ABGs, etc. Once you have a grasp on these labs you can move on to others.

Focus on the # first – once you know WHICH labs you need to know, focus on memorizing the normal ranges. You don’t need to worry too much at this point about the unit of measurement . . . that will come with time. For now just start to learn what the normal ranges are for each of the values.

Understand the “WHY” – in everything we do here at NRSNG we strive to teach you the WHY . . . don’t be satisfied with just the name and normal range . . . that’s baby stuff. Dive into the information and start uncovering WHY the lab value would be ordered. This is the foundation of critical thinking. Getting past simple memorization and really digging to understand why we would order lactic acid on a suspected sepsis patient.

What do elevated and low levels mean – lastly, focus your energy on understanding why a lab value would be high or low. Now that you know why we are ordering the value dig into what it really means if a patient has an elevated level . . . what is causing the hyperkalemia in a renal patient? Why is that going to cause cardiac arrythmias? HgBA1C is elevated in a diabetic patient . . .what does that mean? Why? How does hemoglobin and blood sugar relate?

If you study your labs in this order you will quickly find that not only are you learning them, but you are understanding them and taking part in the care of the patient at a much deeper level.

Many nurses and nursing students stop at the . . . “What values do I NEED to know?” . . . that seems to me like the path of least resistance and doesn’t really get you where you need to be as a nurse.

If you recall, we have spoken a lot about Blooms Taxonomy a lot on NRSNG. The reason for that is that it provides a framework for you to determine how deeply you are critically thinking about a topic and understanding.

Bloom’s Taxonomy is the foundation to critical thinking in nursing and the NCLEX.

A Lifelong Nursing Resource

We have set this page up as a resource that covers nearly every lab value you will encounter . . .

Use the guide above to select a lab value, listen to the podcast, read the post, take notes, and focus on the ones you need to know . . . then come back and start again.

Come back to this page often throughout your career.

Download the free cheatsheet at the top.

Bookmark the page.

And master lab values one by one!

Want a PDF Version To Take With You Anywhere?

Feel free to print it off, stick it in your clinical binder, or just keep it on your phone / tablet for quick access whenever you need it! It’s our free gift to you!